The present invention is related to a method for the operation of a wind energy plant with a control system, which presets a desired value for an electric variable of the wind energy plant to be generated.
From “Erneuerbare Energien May 2006”, pages 39 to 43, the entire contents of which is incorporated herein by reference, it is known that the turbulence intensity depends on the location and the point in time of the measurement. The turbulence intensity is defined as the standard deviation σ of the wind velocity, based on a mean value of the wind velocity. As a measure for the fluctuation of the wind velocity, the turbulence intensity depends on the topology of the location's surroundings, amongst others. The higher the surface roughness in the surroundings of the location, the higher is the turbulence intensity. Higher fluctuations in the wind velocity occur through unequal properties of the ground in the surroundings of the location, which can lead to an increase of the standard deviation σ of the wind velocity. As a result, the turbulence intensity is increased by this. It is further known that additional variables, like weather conditions e.g., neighbouring wind energy plants and also the wave height, in offshore plants, have an influence on the turbulence intensity.
From DE 10 2006 034 106 A1, the entire contents of which is incorporated herein by reference, a method for the operation of a wind turbine is known. In the method, characteristic values for the turbulence are acquired via one or more external sensors. In the wind turbulence cited in the state of the art, it is dealt with a variable, which is according to [0039] depending on the rotor blade position. In [0073], a wind turbulence sensor is mentioned, which measures the turbulences generated on the rotor blade. The wind turbulence is not coincident with the turbulence intensity mentioned above, which depends on the location and the time of the measurement.
The present invention is based on the objective to ensure an operation of the wind energy plant, in which a desired value setting is reduced as rarely as possible without exposing the wind energy plant to unnecessary stresses.